1
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Wang S, Wei Y, Zheng S, Zhang Z, Tang X, Liang L, Zang Z, Qian Q. Beyond the Charge Transfer Mechanism for 2D Materials-Assisted Surface Enhanced Raman Scattering. Anal Chem 2024; 96:9917-9926. [PMID: 38837181 DOI: 10.1021/acs.analchem.4c01051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2024]
Abstract
Two-dimensional (2D) materials have been extensively implemented as surface-enhanced Raman scattering (SERS) substrates, enabling trace-molecule detection for broad applications. However, the accurate understanding of the mechanism remains elusive because most theoretical explanations are still phenomenological or qualitative based on simplified models and rough assumptions. To advance the development of 2D material-assisted SERS, it is vital to attain a comprehensive understanding of the enhancement mechanism and a quantitative assessment of the enhancement performance. Here, the microscopic chemical mechanism of 2D material-assisted SERS is quantitatively investigated. The frequency-dependent Raman scattering cross sections suggest that the 2D materials' SERS performance is strongly dependent on the excitation wavelengths and the molecule types. By analysis of the microscopic Raman scattering processes, the comprehensive contributions of SERS can be revealed. Beyond the widely postulated charge transfer mechanisms, the quantitative results conclusively demonstrate that the resonant transitions within 2D materials alone are also capable of enhancing the molecular Raman scattering through the diffusive scattering of phonons. Furthermore, all of these scattering routines will interfere with each other and determine the final SERS performance. Our results not only provide a complete picture of the SERS mechanisms but also demonstrate a systematic and quantitative approach to theoretically understand, predict, and promote the 2D materials SERS toward analytical applications.
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Affiliation(s)
- Shuo Wang
- Key Laboratory of Optoelectronic Technology and System (Ministry of Education), College of Optoelectronic Engineering, Chongqing University, Chongqing 400044, China
| | - Youchao Wei
- Key Laboratory of Optoelectronic Technology and System (Ministry of Education), College of Optoelectronic Engineering, Chongqing University, Chongqing 400044, China
| | - Siyang Zheng
- Key Laboratory of Optoelectronic Technology and System (Ministry of Education), College of Optoelectronic Engineering, Chongqing University, Chongqing 400044, China
| | - Zhaofu Zhang
- The Institute of Technological Sciences, Wuhan University, Wuhan 430072, China
- Hubei Key Laboratory of Electronic Manufacturing and Packaging Integration, Wuhan University, Wuhan 430072, China
| | - Xi Tang
- Institute of Physical Science and Information Technology, Anhui University, Hefei 230601, China
| | - Liangbo Liang
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Zhigang Zang
- Key Laboratory of Optoelectronic Technology and System (Ministry of Education), College of Optoelectronic Engineering, Chongqing University, Chongqing 400044, China
| | - Qingkai Qian
- Key Laboratory of Optoelectronic Technology and System (Ministry of Education), College of Optoelectronic Engineering, Chongqing University, Chongqing 400044, China
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2
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Wang J, Ling C, Xue X, Ji H, Rong C, Xue Q, Zhou P, Wang C, Lu H, Liu W. Self-Powered and Broadband Photodetectors Based on High-performance Mixed Dimensional Sb 2O 3/PdTe 2/Si Heterojunction for Multiplex Environmental Monitoring. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2310107. [PMID: 38111369 DOI: 10.1002/smll.202310107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 12/07/2023] [Indexed: 12/20/2023]
Abstract
Solar-blind ultraviolet (SBUV) to near-infrared (NIR) broadband photodetectors (BB-PD) have important applications in environmental monitoring and other applications. However, it is challenging to prepare SBUV-IR photosensitive materials via simple steps and to construct SBUV-IR broadband devices for multiplex detection with high sensitivity at different wavelengths. Here, self-powered and broadband photodetectors using a high-performance mixed dimensional Sb2O3 nanorod 1-dimension (1D)/monodisperse microdiamond-like PdTe2 3-dimension (3D)/Si (3D) heterojunction for multiplex detection of environmental pollutants with high sensitivity at broadband wavelength are developed. The 1D/3D mixed dimensional Sb2O3/PdTe2/Si structure combines the advantages of strong light absorption, high carrier transport efficiency of 1D Sb2O3 nanorods, and expansion of interface barrier caused by 3D microdiamond-like PdTe2 interlayer to improve the photocurrent density and self-powered ability. The efficient photogenerated charge separation enables anon/off ratio of more than 5 × 106. The device exhibits excellent photoelectric properties from 255 to 980 nm with the responsivity from 4.56 × 10-2 to 6.55 × 10-1 AW-1, the detectivity from 2.36 × 1012 to 3.39 × 1013 Jones, and the sensitivity from 3.90 × 107 to 1.10 × 1010 cm2 W-1 without external bias. Finally, the proposed device is applied for the multiplex monitoring of environmental pollution gases NO2 with the detection limit of 200 ppb and PM2.5 particles at mild pollution at broadband wavelength. The proposed BB-PD has great potential for multiplex detection of environmental pollutants and other analytes at broadband wavelength.
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Affiliation(s)
- Jingyao Wang
- School of Materials Science and Engineering, China University of Petroleum, Qingdao, 266580, P. R. China
| | - Cuicui Ling
- School of Materials Science and Engineering, China University of Petroleum, Qingdao, 266580, P. R. China
- National Key Laboratory of Deep Oil and Gas, China University of Petroleum (East China), Qingdao, 266580, P. R. China
| | - Xin Xue
- School of Materials Science and Engineering, China University of Petroleum, Qingdao, 266580, P. R. China
| | - Hongguang Ji
- School of Materials Science and Engineering, China University of Petroleum, Qingdao, 266580, P. R. China
| | - Chen Rong
- School of Materials Science and Engineering, China University of Petroleum, Qingdao, 266580, P. R. China
| | - Qingzhong Xue
- School of Materials Science and Engineering, China University of Petroleum, Qingdao, 266580, P. R. China
| | - Peiheng Zhou
- National Engineering Research Center of Electromagnetic Radiation Control Materials, University of Electronic Science and Technology of China, Chengdu, 610054, P. R. China
| | - Chuanke Wang
- Laser fusion research center, Chinese Academy of engineering physics, Mianyang, 621900, P. R. China
| | - Haipeng Lu
- National Engineering Research Center of Electromagnetic Radiation Control Materials, University of Electronic Science and Technology of China, Chengdu, 610054, P. R. China
| | - Wenpeng Liu
- Renal Division and Division of Engineering in Medicine, Department of Medicine, Brigham Women's Hospital, Harvard Medical School, Harvard University, Boston, MA, 02115, USA
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3
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Sovizi S, Angizi S, Ahmad Alem SA, Goodarzi R, Taji Boyuk MRR, Ghanbari H, Szoszkiewicz R, Simchi A, Kruse P. Plasma Processing and Treatment of 2D Transition Metal Dichalcogenides: Tuning Properties and Defect Engineering. Chem Rev 2023; 123:13869-13951. [PMID: 38048483 PMCID: PMC10756211 DOI: 10.1021/acs.chemrev.3c00147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 08/31/2023] [Accepted: 11/09/2023] [Indexed: 12/06/2023]
Abstract
Two-dimensional transition metal dichalcogenides (TMDs) offer fascinating opportunities for fundamental nanoscale science and various technological applications. They are a promising platform for next generation optoelectronics and energy harvesting devices due to their exceptional characteristics at the nanoscale, such as tunable bandgap and strong light-matter interactions. The performance of TMD-based devices is mainly governed by the structure, composition, size, defects, and the state of their interfaces. Many properties of TMDs are influenced by the method of synthesis so numerous studies have focused on processing high-quality TMDs with controlled physicochemical properties. Plasma-based methods are cost-effective, well controllable, and scalable techniques that have recently attracted researchers' interest in the synthesis and modification of 2D TMDs. TMDs' reactivity toward plasma offers numerous opportunities to modify the surface of TMDs, including functionalization, defect engineering, doping, oxidation, phase engineering, etching, healing, morphological changes, and altering the surface energy. Here we comprehensively review all roles of plasma in the realm of TMDs. The fundamental science behind plasma processing and modification of TMDs and their applications in different fields are presented and discussed. Future perspectives and challenges are highlighted to demonstrate the prominence of TMDs and the importance of surface engineering in next-generation optoelectronic applications.
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Affiliation(s)
- Saeed Sovizi
- Faculty of
Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089, Warsaw, Poland
| | - Shayan Angizi
- Department
of Chemistry and Chemical Biology, McMaster
University, Hamilton, Ontario L8S 4M1, Canada
| | - Sayed Ali Ahmad Alem
- Chair in
Chemistry of Polymeric Materials, Montanuniversität
Leoben, Leoben 8700, Austria
| | - Reyhaneh Goodarzi
- School of
Metallurgy and Materials Engineering, Iran
University of Science and Technology (IUST), Narmak, 16846-13114, Tehran, Iran
| | | | - Hajar Ghanbari
- School of
Metallurgy and Materials Engineering, Iran
University of Science and Technology (IUST), Narmak, 16846-13114, Tehran, Iran
| | - Robert Szoszkiewicz
- Faculty of
Chemistry, Biological and Chemical Research Centre, University of Warsaw, Żwirki i Wigury 101, 02-089, Warsaw, Poland
| | - Abdolreza Simchi
- Department
of Materials Science and Engineering and Institute for Nanoscience
and Nanotechnology, Sharif University of
Technology, 14588-89694 Tehran, Iran
- Center for
Nanoscience and Nanotechnology, Institute for Convergence Science
& Technology, Sharif University of Technology, 14588-89694 Tehran, Iran
| | - Peter Kruse
- Department
of Chemistry and Chemical Biology, McMaster
University, Hamilton, Ontario L8S 4M1, Canada
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4
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Shinde PA, Ariga K. Two-Dimensional Nanoarchitectonics for Two-Dimensional Materials: Interfacial Engineering of Transition-Metal Dichalcogenides. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:18175-18186. [PMID: 38047629 DOI: 10.1021/acs.langmuir.3c02929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Transition-metal dichalcogenides (TMDs) have attracted increasing attention in fundamental studies and technological applications owing to their atomically thin thickness, expanded interlayer distance, motif band gap, and phase-transition ability. Even though TMDs have a wide variety of material assets from semiconductor to semimetallic to metallic, the materials with fixed features may not show excellence for precise application. As a result of exclusive crystalline polymorphs, physical and chemical assets of TMDs can be efficiently modified via various approaches of interface nanoarchitectonics, including heteroatom doping, heterostructure, phase engineering, reducing size, alloying, and hybridization. With modified properties, TMDs become interesting materials in diverse fields, including catalysis, energy, electronics, transistors, and optoelectronics.
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Affiliation(s)
- Pragati A Shinde
- Research Center for Materials Nanoarchitectonics, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Katsuhiko Ariga
- Research Center for Materials Nanoarchitectonics, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba 305-0044, Japan
- Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan
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5
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Ahn B, Kim Y, Kim M, Yu HM, Ahn J, Sim E, Ji H, Gul HZ, Kim KS, Ihm K, Lee H, Kim EK, Lim SC. One-Step Passivation of Both Sulfur Vacancies and SiO 2 Interface Traps of MoS 2 Device. NANO LETTERS 2023; 23:7927-7933. [PMID: 37647420 DOI: 10.1021/acs.nanolett.3c01753] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Transition metal dichalcogenides (TMDs) benefit electrical devices with spin-orbit coupling and valley- and topology-related properties. However, TMD-based devices suffer from traps arising from defect sites inside the channel and the gate oxide interface. Deactivating them requires independent treatments, because the origins are dissimilar. This study introduces a single treatment to passivate defects in a multilayer MoS2 FET. By applying back-gate bias, protons from an H-TFSI droplet are injected into the MoS2, penetrating deeply enough to reach the SiO2 gate oxide. The characterizations employing low-temperature transport and deep-level transient spectroscopy (DLTS) studies reveal that the trap density of S vacancies in MoS2 drops to the lowest detection level. The temperature-dependent mobility plot on the SiO2 substrate resembles that of the h-BN substrate, implying that dangling bonds in SiO2 are passivated. The carrier mobility on the SiO2 substrate is enhanced by approximately 2200% after the injection.
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Affiliation(s)
- Byungwook Ahn
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Yoonsok Kim
- Department of Physics, Hanyang University, Seoul 04763, Republic of Korea
- Institute of Plasma Technology, Korea Institute of Fusion Energy, Gunsan 54004, Republic of Korea
| | - Meeree Kim
- Department of Chemistry, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Hyang Mi Yu
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Jaehun Ahn
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Eunji Sim
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Hyunjin Ji
- Department of Electrical Engineering, University of Ulsan, Ulsan 44610, Republic of Korea
| | - Hamza Zad Gul
- Department of Electrical Engineering, Namal University, 30 km Talagang Road, Mianwali 42250, Pakistan
| | - Keun Soo Kim
- Department of Physics and Graphene Research Institute, Sejong University, Seoul 05006, Republic of Korea
| | - Kyuwook Ihm
- Nano & Interface Research Team, Pohang Accelerator Laboratory, Pohang 37673, Republic of Korea
| | - Hyoyoung Lee
- Department of Chemistry, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Eun Kyu Kim
- Department of Physics, Hanyang University, Seoul 04763, Republic of Korea
| | - Seong Chu Lim
- Department of Energy Science, Sungkyunkwan University, Suwon 16419, Republic of Korea
- Department of Smart Fabrication Technology, Sungkyunkwan University, Suwon 16419, Republic of Korea
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6
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Sideri IK, Stangel C, Stergiou A, Liapi A, Ojeda-Galván HJ, Quintana M, Tagmatarchis N. Covalently Modified MoS 2 Bearing a Hamilton-Type Receptor for Recognizing a Redox-Active Ferrocene-Barbiturate Guest via Multiple H-Bonds. Chemistry 2023; 29:e202301474. [PMID: 37249239 DOI: 10.1002/chem.202301474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 05/26/2023] [Accepted: 05/30/2023] [Indexed: 05/31/2023]
Abstract
The covalent modification of the metallic phase of MoS2 with a Hamilton-type ligand is presented, transforming MoS2 to a recognition platform which is able to embrace barbiturate moieties via hydrogen bonding. The successful hydrogen bonding formation is easily monitored by simple electrochemical assessments, if a ferrocene-labeled barbiturate analogue is utilized as a proof of concept. Full spectroscopic, thermal, and electron microscopy imaging characterization is provided for the newly formed recognition system, along with valuable insights concerning the electrochemical sensing. The given methodology expands beyond the sensing applications, confidently entering the territory of supramolecular interactions on the surface of 2D transition metal dichalcogenides. The well-designed host-guest chemistry presented herein, constitutes a guide and an inspiration for hosting customized-structured functional building blocks on MoS2 and its relatives via hydrogen bonding, opening up new opportunities regarding potential applications.
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Affiliation(s)
- Ioanna K Sideri
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635, Athens, Greece
| | - Christina Stangel
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635, Athens, Greece
| | - Anastasios Stergiou
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635, Athens, Greece
| | - Alexandra Liapi
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635, Athens, Greece
| | - Hiram Joazet Ojeda-Galván
- High Resolution Microscopy-CICSaB and Faculty of Science, Universidad Autonóma de San Luis Potosi, Av. Sierra Leona 550, 78210, Lomas de San Luis Potosi, SLP, Mexico
| | - Mildred Quintana
- High Resolution Microscopy-CICSaB and Faculty of Science, Universidad Autonóma de San Luis Potosi, Av. Sierra Leona 550, 78210, Lomas de San Luis Potosi, SLP, Mexico
| | - Nikos Tagmatarchis
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635, Athens, Greece
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7
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Zheng Y, Cao B, Tang X, Wu Q, Wang W, Li G. Vertical 1D/2D Heterojunction Architectures for Self-Powered Photodetection Application: GaN Nanorods Grown on Transition Metal Dichalcogenides. ACS NANO 2022; 16:2798-2810. [PMID: 35084838 DOI: 10.1021/acsnano.1c09791] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Van der Waals (vdW) heterojunctions based on two-dimensional (2D) transition metal dichalcogenide (TMD) materials have attracted the attention of researchers to conduct fundamental investigations on emerging physical phenomena and expanding diverse nano-optoelectronic devices. Herein, the quasi-van der Waals epitaxial (QvdWE) growth of vertically aligned one-dimensional (1D) GaN nanorod arrays (NRAs) on TMDs/Si substrates is reported, and their vdW heterojunctions in the applications of high-performance self-powered photodetection are demonstrated accordingly. Such 1D/2D hybrid systems fully combine the advantages of the strong light absorption of 1D GaN nanoarrays and the excellent electrical properties of 2D TMD materials, boosting the photogenerated current density, which demonstrates a light on/off ratio above 105. The device exhibits a competitive photovoltaic photoresponsivity over 10 A W-1 under a weak detectable light signal without any external bias, which is attributed to the efficient photogenerated charge separation under the strong built-in potential from the type-II band alignment of GaN NRAs/TMDs. This work presents a QvdWE route to prepare 1D/2D heterostructures for the fabrication of self-powered photodetectors, which shows promising potentials for practical applications of space communications, sensing networks, and environmental monitoring.
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Affiliation(s)
- Yulin Zheng
- State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China
| | - Ben Cao
- State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China
| | - Xin Tang
- State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China
| | - Qing Wu
- State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China
| | - Wenliang Wang
- State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China
- Department of Electronic Materials, School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China
| | - Guoqiang Li
- State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China
- Department of Electronic Materials, School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China
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8
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Li Z, Bretscher H, Zhang Y, Delport G, Xiao J, Lee A, Stranks SD, Rao A. Mechanistic insight into the chemical treatments of monolayer transition metal disulfides for photoluminescence enhancement. Nat Commun 2021; 12:6044. [PMID: 34663820 PMCID: PMC8523741 DOI: 10.1038/s41467-021-26340-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 09/17/2021] [Indexed: 11/29/2022] Open
Abstract
There is a growing interest in obtaining high quality monolayer transition metal disulfides for optoelectronic applications. Surface treatments using a range of chemicals have proven effective to improve the photoluminescence yield of these materials. However, the underlying mechanism for the photoluminescence enhancement is not clear, which prevents a rational design of passivation strategies. Here, a simple and effective approach to significantly enhance the photoluminescence is demonstrated by using a family of cation donors, which we show to be much more effective than commonly used p-dopants. We develop a detailed mechanistic picture for the action of these cation donors and demonstrate that one of them, bis(trifluoromethane)sulfonimide lithium salt (Li-TFSI), enhances the photoluminescence of both MoS2 and WS2 to a level double that of the currently best performing super-acid trifluoromethanesulfonimide (H-TFSI) treatment. In addition, the ionic salts used in our treatments are compatible with greener solvents and are easier to handle than super-acids, providing the possibility of performing treatments during device fabrication. This work sets up rational selection rules for ionic chemicals to passivate transition metal disulfides and increases their potential in practical optoelectronic applications.
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Affiliation(s)
- Zhaojun Li
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, CB3 0HE, Cambridge, UK
- Molecular and Condensed Matter Physics, Department of Physics and Astronomy, Uppsala University, 75120, Uppsala, Sweden
| | - Hope Bretscher
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, CB3 0HE, Cambridge, UK
| | - Yunwei Zhang
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, CB3 0HE, Cambridge, UK
| | - Géraud Delport
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, CB3 0HE, Cambridge, UK
| | - James Xiao
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, CB3 0HE, Cambridge, UK
| | - Alpha Lee
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, CB3 0HE, Cambridge, UK
| | - Samuel D Stranks
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, CB3 0HE, Cambridge, UK
- Department of Chemical Engineering & Biotechnology, University of Cambridge, Philippa Fawcett Drive, CB3 0AS, Cambridge, UK
| | - Akshay Rao
- Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, CB3 0HE, Cambridge, UK.
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9
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Chen X, Kohring M, Assebban M, Tywoniuk B, Bartlam C, Moses Badlyan N, Maultzsch J, Duesberg GS, Weber HB, Knirsch KC, Hirsch A. Covalent Patterning of 2D MoS 2. Chemistry 2021; 27:13117-13122. [PMID: 34357651 PMCID: PMC8518675 DOI: 10.1002/chem.202102021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Indexed: 11/15/2022]
Abstract
The development of an efficient method to patterning 2D MoS2 into a desired topographic structure is of particular importance to bridge the way towards the ultimate device. Herein, we demonstrate a patterning strategy by combining the electron beam lithography with the surface covalent functionalization. This strategy allows us to generate delicate MoS2 ribbon patterns with a minimum feature size of 2 μm in a high throughput rate. The patterned monolayer MoS2 domain consists of a spatially well‐defined heterophase homojunction and alternately distributed surface characteristics, which holds great interest for further exploration of MoS2 based devices.
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Affiliation(s)
- Xin Chen
- Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Nikolaus-Fiebiger-Straße 10, 91058, Erlangen, Germany
| | - Malte Kohring
- Department of Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Staudtstr.7, 91058, Erlangen, Germany
| | - M'hamed Assebban
- Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Nikolaus-Fiebiger-Straße 10, 91058, Erlangen, Germany
| | - Bartłomiej Tywoniuk
- Institute of Physics, EIT 2, Faculty of Electrical Engineering and Information Technology, Universität der Bundeswehr, 85579, Neubiberg, Germany
| | - Cian Bartlam
- Institute of Physics, EIT 2, Faculty of Electrical Engineering and Information Technology, Universität der Bundeswehr, 85579, Neubiberg, Germany
| | - Narine Moses Badlyan
- Department of Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Staudtstr.7, 91058, Erlangen, Germany
| | - Janina Maultzsch
- Department of Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Staudtstr.7, 91058, Erlangen, Germany
| | - Georg S Duesberg
- Institute of Physics, EIT 2, Faculty of Electrical Engineering and Information Technology, Universität der Bundeswehr, 85579, Neubiberg, Germany
| | - Heiko B Weber
- Department of Physics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Staudtstr.7, 91058, Erlangen, Germany
| | - Kathrin C Knirsch
- Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Nikolaus-Fiebiger-Straße 10, 91058, Erlangen, Germany
| | - Andreas Hirsch
- Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Nikolaus-Fiebiger-Straße 10, 91058, Erlangen, Germany
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10
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Chen X, Bartlam C, Lloret V, Moses Badlyan N, Wolff S, Gillen R, Stimpel‐Lindner T, Maultzsch J, Duesberg GS, Knirsch KC, Hirsch A. Covalent Bisfunctionalization of Two‐Dimensional Molybdenum Disulfide. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202103353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Xin Chen
- Department of Chemistry and Pharmacy Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg Nikolaus-Fiebiger-Strasse 10 91058 Erlangen Germany
| | - Cian Bartlam
- Institute of Physics Faculty of Electrical Engineering and Information Technology Universität der Bundeswehr München Werner-Heisenberg-Weg 39 85577 Neubiberg Germany
| | - Vicent Lloret
- Department of Chemistry and Pharmacy Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg Nikolaus-Fiebiger-Strasse 10 91058 Erlangen Germany
| | - Narine Moses Badlyan
- Department of Physics Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg Staudtstrasse 7 91058 Erlangen Germany
| | - Stefan Wolff
- Department of Physics Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg Staudtstrasse 7 91058 Erlangen Germany
| | - Roland Gillen
- Department of Physics Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg Staudtstrasse 7 91058 Erlangen Germany
| | - Tanja Stimpel‐Lindner
- Institute of Physics Faculty of Electrical Engineering and Information Technology Universität der Bundeswehr München Werner-Heisenberg-Weg 39 85577 Neubiberg Germany
| | - Janina Maultzsch
- Department of Physics Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg Staudtstrasse 7 91058 Erlangen Germany
| | - Georg S. Duesberg
- Institute of Physics Faculty of Electrical Engineering and Information Technology Universität der Bundeswehr München Werner-Heisenberg-Weg 39 85577 Neubiberg Germany
| | - Kathrin C. Knirsch
- Department of Chemistry and Pharmacy Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg Nikolaus-Fiebiger-Strasse 10 91058 Erlangen Germany
| | - Andreas Hirsch
- Department of Chemistry and Pharmacy Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg Nikolaus-Fiebiger-Strasse 10 91058 Erlangen Germany
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11
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Stergiou A, Stangel C, Canton-Vitoria R, Kitaura R, Tagmatarchis N. An ion-selective crown ether covalently grafted onto chemically exfoliated MoS 2 as a biological fluid sensor. NANOSCALE 2021; 13:8948-8957. [PMID: 33960349 DOI: 10.1039/d1nr00404b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
We describe the basal plane functionalization of chemically exfoliated molybdenum disulfide (ce-MoS2) nanosheets with a benzo-15-crown-5 ether (B15C5), promoted by the chemistry of diazonium salts en route to the fabrication and electrochemical assessment of an ion-responsive electrode. The success of the chemical modification of ce-MoS2 nanosheets was investigated by infrared and Raman spectroscopy, and the amount of the incorporated crown ether was estimated by thermogravimetric analysis. Raman spatial mapping at on-resonance excitation allowed us to disclose the structural characteristics of the functionalized B15C5-MoS2 nanosheets and the impact of basal plane functionalization to the stabilization of the 1T phase of ce-MoS2. Morphological investigation of the B15C5-MoS2 hybrid was implemented by atomic force microscopy and high-resolution transmission electron microscopy. Furthermore, fast-Fourier-transform analysis and in situ energy dispersive X-ray spectroscopy revealed the crystal lattice of the modified nanosheets and the presence of crown-ether addends, respectively. Finally, B15C5-MoS2 electrodes were constructed and evaluated as ion-selective electrodes for sodium ions in aqueous solution and an artificial sweat matrix.
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Affiliation(s)
- Anastasios Stergiou
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece.
| | - Christina Stangel
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece.
| | | | - Ryo Kitaura
- Department of Chemistry, Nagoya University, Nagoya 464-8602, Japan
| | - Nikos Tagmatarchis
- Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece.
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12
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Patil V, Kim J, Agrawal K, Park T, Yi J, Aoki N, Watanabe K, Taniguchi T, Kim GH. High mobility field-effect transistors based on MoS 2crystals grown by the flux method. NANOTECHNOLOGY 2021; 32:325603. [PMID: 33845468 DOI: 10.1088/1361-6528/abf6f1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 04/12/2021] [Indexed: 06/12/2023]
Abstract
Two-dimensional (2D) molybdenum disulphide (MoS2) transition metal dichalcogenides (TMDs) have great potential for use in optical and electronic device applications; however, the performance of MoS2is limited by its crystal quality, which serves as a measure of the defects and grain boundaries in the grown material. Therefore, the high-quality growth of MoS2crystals continues to be a critical issue. In this context, we propose the formation of high-quality MoS2crystals via the flux method. The resulting electrical properties demonstrate the significant impact of crystal morphology on the performance of MoS2field-effect transistors. MoS2made with a relatively higher concentration of sulphur (a molar ratio of 2.2) and at a cooling rate of 2.5 °C h-1yielded good quality and optimally sized crystals. The room-temperature and low-temperature (77 K) electrical transport properties of MoS2field-effect transistors (FETs) were studied in detail, with and without the use of a hexagonal boron nitride (h-BN) dielectric to address the mobility degradation issue due to scattering at the SiO2/2D material interface. A maximum field-effect mobility of 113 cm2V-1s-1was achieved at 77 K for the MoS2/h-BN FET following high-quality crystal formation by the flux method. Our results confirm the achievement of large-scale high-quality crystal growth with reduced defect density using the flux method and are key to achieving higher mobility in MoS2FET devices in parallel with commercially accessible MoS2crystals.
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Affiliation(s)
- Vilas Patil
- School of Electronic and Electrical Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
- Department of Condensed Matter Physics and Materials Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India
| | - Jihyun Kim
- Centre for Quantum Materials and Superconductivity (CQMS), Department of Physics, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Khushabu Agrawal
- School of Electronic and Electrical Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
| | - Tuson Park
- Centre for Quantum Materials and Superconductivity (CQMS), Department of Physics, Sungkyunkwan University, Suwon 16419, Republic of Korea
| | - Junsin Yi
- School of Electronic and Electrical Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
| | - Nobuyuki Aoki
- Department of Materials Science, Chiba University, Chiba 263-8522, Japan
| | - Kenji Watanabe
- Research Centre for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Takashi Taniguchi
- International Centre for Materials Nano-Architectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Gil-Ho Kim
- School of Electronic and Electrical Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
- Sungkyunkwan Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University, Suwon 16419, Republic of Korea
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13
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Chen X, Bartlam C, Lloret V, Moses Badlyan N, Wolff S, Gillen R, Stimpel-Lindner T, Maultzsch J, Duesberg GS, Knirsch KC, Hirsch A. Covalent Bisfunctionalization of Two-Dimensional Molybdenum Disulfide. Angew Chem Int Ed Engl 2021; 60:13484-13492. [PMID: 33768735 PMCID: PMC8251601 DOI: 10.1002/anie.202103353] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Indexed: 12/02/2022]
Abstract
Covalent functionalization of two‐dimensional molybdenum disulfide (2D MoS2) holds great promise in developing robust organic‐MoS2 hybrid structures. Herein, for the first time, we demonstrate an approach to building up a bisfunctionalized MoS2 hybrid structure through successively reacting activated MoS2 with alkyl iodide and aryl diazonium salts. This approach can be utilized to modify both colloidal and substrate supported MoS2 nanosheets. We have discovered that compared to the adducts formed through the reactions of MoS2 with diazonium salts, those formed through the reactions of MoS2 with alkyl iodides display higher reactivity towards further reactions with electrophiles. We are convinced that our systematic study on the formation and reactivity of covalently functionalized MoS2 hybrids will provide some practical guidance on multi‐angle tailoring of the properties of 2D MoS2 for various potential applications.
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Affiliation(s)
- Xin Chen
- Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Nikolaus-Fiebiger-Strasse 10, 91058, Erlangen, Germany
| | - Cian Bartlam
- Institute of Physics, Faculty of Electrical Engineering and Information Technology, Universität der Bundeswehr München, Werner-Heisenberg-Weg 39, 85577, Neubiberg, Germany
| | - Vicent Lloret
- Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Nikolaus-Fiebiger-Strasse 10, 91058, Erlangen, Germany
| | - Narine Moses Badlyan
- Department of Physics, Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Staudtstrasse 7, 91058, Erlangen, Germany
| | - Stefan Wolff
- Department of Physics, Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Staudtstrasse 7, 91058, Erlangen, Germany
| | - Roland Gillen
- Department of Physics, Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Staudtstrasse 7, 91058, Erlangen, Germany
| | - Tanja Stimpel-Lindner
- Institute of Physics, Faculty of Electrical Engineering and Information Technology, Universität der Bundeswehr München, Werner-Heisenberg-Weg 39, 85577, Neubiberg, Germany
| | - Janina Maultzsch
- Department of Physics, Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Staudtstrasse 7, 91058, Erlangen, Germany
| | - Georg S Duesberg
- Institute of Physics, Faculty of Electrical Engineering and Information Technology, Universität der Bundeswehr München, Werner-Heisenberg-Weg 39, 85577, Neubiberg, Germany
| | - Kathrin C Knirsch
- Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Nikolaus-Fiebiger-Strasse 10, 91058, Erlangen, Germany
| | - Andreas Hirsch
- Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Nikolaus-Fiebiger-Strasse 10, 91058, Erlangen, Germany
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14
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Kozhakhmetov A, Schuler B, Tan AMZ, Cochrane KA, Nasr JR, El-Sherif H, Bansal A, Vera A, Bojan V, Redwing JM, Bassim N, Das S, Hennig RG, Weber-Bargioni A, Robinson JA. Scalable Substitutional Re-Doping and its Impact on the Optical and Electronic Properties of Tungsten Diselenide. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e2005159. [PMID: 33169451 DOI: 10.1002/adma.202005159] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 10/12/2020] [Indexed: 06/11/2023]
Abstract
Reliable, controlled doping of 2D transition metal dichalcogenides will enable the realization of next-generation electronic, logic-memory, and magnetic devices based on these materials. However, to date, accurate control over dopant concentration and scalability of the process remains a challenge. Here, a systematic study of scalable in situ doping of fully coalesced 2D WSe2 films with Re atoms via metal-organic chemical vapor deposition is reported. Dopant concentrations are uniformly distributed over the substrate surface, with precisely controlled concentrations down to <0.001% Re achieved by tuning the precursor partial pressure. Moreover, the impact of doping on morphological, chemical, optical, and electronic properties of WSe2 is elucidated with detailed experimental and theoretical examinations, confirming that the substitutional doping of Re at the W site leads to n-type behavior of WSe2 . Transport characteristics of fabricated back-gated field-effect-transistors are directly correlated to the dopant concentration, with degrading device performances for doping concentrations exceeding 1% of Re. The study demonstrates a viable approach to introducing true dopant-level impurities with high precision, which can be scaled up to batch production for applications beyond digital electronics.
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Affiliation(s)
- Azimkhan Kozhakhmetov
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Bruno Schuler
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- nanotech@surfaces Laboratory, Empa-Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, 8600, Switzerland
| | - Anne Marie Z Tan
- Department of Materials Science and Engineering, University of Florida, Gainesville, FL, 32611, USA
| | - Katherine A Cochrane
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Joseph R Nasr
- Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Hesham El-Sherif
- Department of Materials Science and Engineering, McMaster University, Hamilton, ON, L8S 4L8, Canada
| | - Anushka Bansal
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Alex Vera
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Vincent Bojan
- Materials Research Institute, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Joan M Redwing
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
- Two-Dimensional Crystal Consortium, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Nabil Bassim
- Department of Materials Science and Engineering, McMaster University, Hamilton, ON, L8S 4L8, Canada
| | - Saptarshi Das
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
- Department of Engineering Science and Mechanics, The Pennsylvania State University, University Park, PA, 16802, USA
- Materials Research Institute, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Richard G Hennig
- Department of Materials Science and Engineering, University of Florida, Gainesville, FL, 32611, USA
| | | | - Joshua A Robinson
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA, 16802, USA
- Two-Dimensional Crystal Consortium, The Pennsylvania State University, University Park, PA, 16802, USA
- Center for 2-Dimensional and Layered Materials, The Pennsylvania State University, University Park, PA, 16802, USA
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15
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Guo H, Zhang Z, Huang B, Wang X, Niu H, Guo Y, Li B, Zheng R, Wu H. Theoretical study on the photocatalytic properties of 2D InX(X = S, Se)/transition metal disulfide (MoS 2 and WS 2) van der Waals heterostructures. NANOSCALE 2020; 12:20025-20032. [PMID: 32996977 DOI: 10.1039/d0nr04725b] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Harvesting solar energy for artificial photosynthesis is an emerging field in alternative energy research. In this work, the photocatalytic properties of InX(X = S, Se)/transition metal disulfide (MoS2 and WS2) van der Waals heterostructures have been investigated. The calculation results indicate that these heterostructures exhibit improved photocatalytic performance over that of isolated InX or transition metal disulfide monolayers. The studied heterostructures all have type-II band alignment with holes and electrons located at the TMD and InX side, respectively. This facilitates the spatial separation of photogenerated carriers and improves the photocatalytic efficiency. The carrier mobility of the designed heterostructures can be boosted compared with the isolated monolayers, thus enhancing the carrier transport properties. Moreover, the strain-tuned heterostructures can prominently manipulate the light-harvesting capability especially from the visible light to infrared light range. Among the studied heterostructures, InSe/MoS2 with the suitable band edge positions, excellent transport properties and strain tolerance, and the lowest overpotential for oxygen evolution, stands out as the most promising candidate for photocatalytic applications. This work opens an avenue for the design of highly efficient heterostructure photocatalysts for solar-to-energy applications.
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Affiliation(s)
- Hailing Guo
- College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China.
| | - Zhaofu Zhang
- Department of Engineering, University of Cambridge, Cambridge, CB2 1PZ, UK
| | - Bingquan Huang
- College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China.
| | - Xiting Wang
- School of Electrical Engineering, Wuhan University, Wuhan, 430072, China
| | - Huan Niu
- School of Electrical Engineering, Wuhan University, Wuhan, 430072, China
| | - Yuzheng Guo
- School of Electrical Engineering, Wuhan University, Wuhan, 430072, China
| | - Baikui Li
- College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China.
| | - Ruisheng Zheng
- College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China.
| | - Honglei Wu
- College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China.
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16
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Liu X, Zhang Z, Lv B, Ding Z, Luo Z. The External Electric Field-Induced Tunability of the Schottky Barrier Height in Graphene/AlN Interface: A Study by First-Principles. NANOMATERIALS (BASEL, SWITZERLAND) 2020; 10:E1794. [PMID: 32916951 PMCID: PMC7558498 DOI: 10.3390/nano10091794] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 09/06/2020] [Accepted: 09/09/2020] [Indexed: 01/02/2023]
Abstract
Graphene-based van der Waals (vdW) heterojunction plays an important role in next-generation optoelectronics, nanoelectronics, and spintronics devices. The tunability of the Schottky barrier height (SBH) is beneficial for improving device performance, especially for the contact resistance. Herein, we investigated the electronic structure and interfacial characteristics of the graphene/AlN interface based on density functional theory. The results show that the intrinsic electronic properties of graphene changed slightly after contact. In contrast, the valence band maximum of AlN changed significantly due to the hybridization of Cp and Np orbital electrons. The Bader charge analysis showed that the electrons would transfer from AlN to graphene, implying that graphene would induce acceptor states. Additionally, the Schottky contact nature can be effectively tuned by the external electric field, and it will be tuned from the p-type into n-type once the electric field is larger than about 0.5 V/Å. Furthermore, the optical absorption of graphene/AlN is enhanced after contact. Our findings imply that the SBH is controllable, which is highly desirable in nano-electronic devices.
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Affiliation(s)
- Xuefei Liu
- Key Laboratory of Low Dimensional Condensed Matter Physics of Higher Educational Institution of Guizhou Province, Guizhou Normal University, Guiyang 550025, China; (X.L.); (B.L.)
| | - Zhaocai Zhang
- Beijing Institute of Space Science and Technology Information, Beijing 100094, China;
| | - Bing Lv
- Key Laboratory of Low Dimensional Condensed Matter Physics of Higher Educational Institution of Guizhou Province, Guizhou Normal University, Guiyang 550025, China; (X.L.); (B.L.)
| | - Zhao Ding
- College of Big data and Information Engineering, Guizhou University, Guiyang 550025, China;
| | - Zijiang Luo
- College of Information, Guizhou University Finance and Economics, Guiyang 550025, China
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17
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Controlling the Structural, Mechanical and Frictional Properties of MoSx Coatings by High-Power Impulse Magnetron Sputtering. COATINGS 2020. [DOI: 10.3390/coatings10080755] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Tribology, as the science and technology of interacting surfaces, typically relies on liquid lubricants which reduce friction and wear. For environmentally friendly tribological purposes and applications requiring a liquid-free performance, solid lubricants, such as MoS2 coatings, play an essential role. It is crucial to understand the interplay between the parameters of the coating synthesis and the characteristics of the coating. The impact of the deposition parameters on the structural, mechanical and frictional properties of MoSx thin films, which are synthesized by high-power impulse magnetron sputtering, are studied. The morphology, topography and stoichiometry (2.02 < x < 2.22) of the films are controlled by, in particular, the bias-voltage and heating power applied during the sputtering process. In combination with a low pulse frequency the hardness and elastic stiffness of the MoSx films are enhanced up to 2 and 90 GPa, respectively. This enhancement is assigned to a shortening of the Mo-S bonding lengths and a strengthening in the interatomic coupling as well as to a formation of small-sized crystallites at the surface. The friction coefficient reduces to µ = 0.10 for films with an initial (100) orientation and the mean roughness of the MoSx films decreases below 15 nm by shortening the cathode pulses.
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18
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Chen X, Denninger P, Stimpel-Lindner T, Spiecker E, Duesberg GS, Backes C, Knirsch KC, Hirsch A. Defect Engineering of Two-Dimensional Molybdenum Disulfide. Chemistry 2020; 26:6535-6544. [PMID: 32141636 PMCID: PMC7317841 DOI: 10.1002/chem.202000286] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Indexed: 01/06/2023]
Abstract
Two‐dimensional (2D) molybdenum disulfide (MoS2) holds great promise in electronic and optoelectronic applications owing to its unique structure and intriguing properties. The intrinsic defects such as sulfur vacancies (SVs) of MoS2 nanosheets are found to be detrimental to the device efficiency. To mitigate this problem, functionalization of 2D MoS2 using thiols has emerged as one of the key strategies for engineering defects. Herein, we demonstrate an approach to controllably engineer the SVs of chemically exfoliated MoS2 nanosheets using a series of substituted thiophenols in solution. The degree of functionalization can be tuned by varying the electron‐withdrawing strength of substituents in thiophenols. We find that the intensity of 2LA(M) peak normalized to A1g peak strongly correlates to the degree of functionalization. Our results provide a spectroscopic indicator to monitor and quantify the defect engineering process. This method of MoS2 defect functionalization in solution also benefits the further exploration of defect‐free MoS2 for a wide range of applications.
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Affiliation(s)
- Xin Chen
- Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Nikolaus-Fiebiger-Straße 10, 91058, Erlangen, Germany
| | - Peter Denninger
- Center for Nanoanalysis and Electron Microscopy (CENEM) &, Institute of Micro- and Nanostructure Research (IMN), Interdisciplinary Center for Nanostructured Films (IZNF), Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Cauerstraße 3, 91058, Erlangen, Germany
| | - Tanja Stimpel-Lindner
- Institute of Physics, EIT 2, Faculty of Electrical Engineering and Information Technology, Universität der Bundeswehr, 85579, Neubiberg, Germany
| | - Erdmann Spiecker
- Center for Nanoanalysis and Electron Microscopy (CENEM) &, Institute of Micro- and Nanostructure Research (IMN), Interdisciplinary Center for Nanostructured Films (IZNF), Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Cauerstraße 3, 91058, Erlangen, Germany
| | - Georg S Duesberg
- Institute of Physics, EIT 2, Faculty of Electrical Engineering and Information Technology, Universität der Bundeswehr, 85579, Neubiberg, Germany
| | - Claudia Backes
- Institute of Physical Chemistry, Heidelberg University, Im Neuenheimer Feld 253, 69120, Heidelberg, Germany
| | - Kathrin C Knirsch
- Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Nikolaus-Fiebiger-Straße 10, 91058, Erlangen, Germany
| | - Andreas Hirsch
- Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Nikolaus-Fiebiger-Straße 10, 91058, Erlangen, Germany
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19
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Fang L, Liang W, Feng Q, Luo SN. Structural engineering of bilayer PtSe 2 thin films: a first-principles study. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:455001. [PMID: 31341102 DOI: 10.1088/1361-648x/ab34bc] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
PtSe2 is an emerging layered two-dimensional material of applied interest. Its monolayer shows promising properties for applications in electronic devices, while the bandgap of a multilayer PtSe2 film can be tuned via changing its thickness. In this work the bilayer PtSe2 thin films are investigated as an example of structural engineering with first-principles calculations. Various van der Waals corrections schemes are firstly discussed, and the optB86b scheme shows a better description of the semiconductor-metal transition for PtSe2 films. Six bilayer PtSe2 thin films in different stacking modes are constructed in order to structurally tune the electronic and transport properties. The bandgap can be effectively broadened with the structural engineering for wider potential applications. The carrier mobility, dynamical stability and Raman spectra are also calculated and discussed.
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Affiliation(s)
- Limei Fang
- Key Laboratory of Advanced Technologies of Materials, Ministry of Education, and Institute of Materials Dynamics, Southwest Jiaotong University, Chengdu, Sichuan 610031, People's Republic of China
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20
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Investigation of the Tribofilm Formation of HiPIMS Sputtered MoSx Thin Films in Different Environments by Raman Scattering. LUBRICANTS 2019. [DOI: 10.3390/lubricants7110100] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Understanding the generation of third body particles and their contribution to the formation of tribofilms of MoSx thin films is still challenging due to a large number of influencing factors. Besides the structure of the as-deposited MoSx films, the environment and the conditions during the Ball-on-disk tests affect tribofilms and thus the friction. Therefore, the influence of the surface pressure and sliding velocity in air, argon and nitrogen environments on the generation of the third body particles and the tribofilm formation of randomly oriented MoSx films is investigated. A high surface pressure is one major factor to achieve low friction, especially under humid conditions, which is important considering the use in industrial applications, for example dry-running screw machines. However, the mechanisms leading to that frictional behavior are still affected by the surrounding environment. While low friction is caused by a more extensive tribofilm formation in air, in argon and nitrogen, large size third body particles dispensed all over the contact area contribute to a lower friction. Raman scattering reveal a different chemistry of these particles reflected in the absence of laser- or temperature-induced surface oxidation compared to the as-deposited film and the wear track. The Raman scattering results are discussed with respect to the wear particle size, its chemical reactivity and strain-induced bonding changes.
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21
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Huang N, Peng R, Ding Y, Yan S, Li G, Sun P, Sun X, Liu X, Yu H. Facile chemical-vapour-deposition synthesis of vertically aligned co-doped MoS2 nanosheets as an efficient catalyst for triiodide reduction and hydrogen evolution reaction. J Catal 2019. [DOI: 10.1016/j.jcat.2019.04.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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